Per PI no participants enrolled

This phase II trial studies how well gallium-68 PSMA-11 PET/CT or PET/MRI works in finding prostate cancer cells that have come back (recurrent) in patients with prostate cancer. Gallium-68 PSMA-11 is a type of radioactive compound, called a radiotracer, which is injected in the vein and can accumulate in tumor cells to generate a signal detected by PET/CT or PET/MRI imaging. This may help researchers in finding recurrent prostate cancer cells in patients with prostate cancer.

PRIMARY OBJECTIVE:

I. To assess the positive predictive value (PPV) of gallium Ga 68-labeled PSMA-11 (68Ga-PSMA11) positron emission tomography/computed tomography (PET/CT) and positron emission tomography/magnetic resonance imaging (PET/MRI) on a patient level using histopathology or confirmatory imaging as a standard of truth (SoT).

SECONDARY OBJECTIVES:

I. To assess the PPV per-patient for 68Ga-PSMA-11 PET/CT and PET/MRI detection of tumor location confirmed by histopathology/biopsy alone.

II. Demonstrate the safety of 68Ga-PSMA-11 PET/CT or PET/MRI imaging in participants with prostate cancer.

III. Demonstrate the efficacy of 68Ga-PSMA-11 PET/CT or PET/MRI imaging to monitor response to treatment in participants with prostate cancer.

OUTLINE:

Patients receive gallium 68Ga-PSMA-11 intravenously (IV). 50-100 minutes after injection, patients then undergo a PET/CT scan or PET/MRI scan over 60 minutes.

After completion of study, patients are followed up at 30 and 90 days, then between 3-36 months.

Inclusion Criteria:

• Pathologically proven prostate cancer
• Rising prostate-specific antigen (PSA) after definitive therapy with prostatectomy or radiation therapy (external beam or brachytherapy)
• Karnofsky performance status (KPS) >= 50 (Eastern Cooperative Oncology Group [ECOG]/World Health Organization [WHO] 0, 1, or 2)
• Ability to understand and willingness to provide informed consent
• Participants with known metastatic prostate cancer planned to undergo active systemic treatment

Exclusion Criteria:

• Unable to lie flat, still, or tolerate a PET or MRI scan
• Contraindication to optional furosemide administration including prior allergy or adverse reaction to furosemide or sulfa drugs. This exclusion criteria can be removed if furosemide is omitted as part of the PET imaging protocol if a second-generation scatter correction - (defined as either Ga-68 specific prompt gamma correction or multiple scatter model) is available for the used PET device